I know we have other "ifeq" like this (like for "production") but this breaks when running several goals from the command line and I think we should support this.

You can probably use target-specific variables instead:
```make
reset-gaia: GAIA_INSTALL_PARENT ?= /system/b2g
```

see https://www.gnu.org/software/make/manual/html_node/Target_002dspecific.html for more information